在PC机上模拟PLC实现MODBUS通信

Communication on PC to simulate PLC with MODBUS

独立的计算机控制单元与工业控制网络互连时，可将其模拟成为ＰＬＣ，然后利用ＰＬＣ的通信协议，与工业控制网络进行数据通信，从而为传统仪表与控制网络互连问题提供了新的解决方法和思路。本文以ＭＯＤＢＵＳ通信协议为例，对此进行有意义的探讨。同时介绍了ＭＯＤＢＵＳ通信协议的基本内容和格式，并给出了在 Ｖｉｓｕａｌ Ｂａｓｉｃ下实现通信的方法。

When connected in the industrial control net, the computer can be simulated as a PLC. It exchanges data on line by using PlC's communication protocol. It is a new method or idea to the problem of link traditional devices with modern control net. The paper takes the MODBUS communication as an example, and has a deep probing on it. At the same time, introduces the main content and format of MODBUS protocol, and the diagram of communication with Visual Basic.